Bolster supporting mechanism



Nov. 10, 1936. M. B. HALL BOLSTER SUPPORTING MECHANISM Filed May 1, 19:55

.Eauentor Patented Nov 10, 1936 UNITED .sTATES;

PATE ToFFicE nons'ran SUPPORTING Mncnsmistr Marchand 3-. Hall, Chicago, Ili.,' asslgnor to Cardwell-Westinghouse 111., 'a corporation of- Delaware.

Company, Chicago,

Application May 1, 1933, Serial No.'6ii8,684

6Clalms. (Cl. 261-9)- This invention relates to shock absorbers, and,

' spring seats in parallel relation during the operation of. the device. a

A further object-of the invention is the provision of a new and improved'shock absorber in 15 which the resistance increases rapidly upon compression of the device and in" which the rebound is dampened.

A furtherobj ect of the invention is the provisionof a new and improved shock absorbing 2o device that is simple in. construction, inexpensiveto manufacture and install, e'fficient in operation and not likely to become broken or 'out-of-r'epair. Other and further objects and advantages of the invention will appear from the following de-l scription taken in connection with the accompanying drawing, in which- Fi 1' is a side elevation of a. portion of a rail-- In the'use of bolster springs of the combined friction and resilient type on railway cars, itis not uncommon under certain eonditions'for the 4 upper spring seat to assume arrangular position 4 relative to the lower spring seat, and thereby un-v equally distribute the load on the spring. The

present' invention seeks to remedy this difliculty by the provision of means for automatically positioning the spring plates at the ends of the gear whereby the plates will remain substantially parallel during the use of the device. f

Referring now to-the drawing, the reference character l0 designates generally a railway car truck having a side=frame I I, lower arch member 50 I2" and pedestals l3 and H, as is usual in such constructions. Vertically slidable between the pedestals I3 and I4 is the bolster l5 which is sup-1 ported by the bolster supporting units l6 inserted between the spring plank l1 and the bolster sup- 55 porting unit. Each bolster supporting unit comprises a friction device l3 anda spring ID. The friction device comprises two frictionally engaging telescopicv members. This device includes-a.- lower section 2 lcomprising a base plate 22 which is adapted to be seated on the spring plank l1 5 and a cylindrical hollow member 23 rigidly secured to said plate and extending upwardly therefrom. I I The interior surface of the cylindrical member 23 tapers downwardly to form a friction surface,

'as will presently appear. The plate 22 is provided at its central portion with an upstanding hollow projection or boss 24 extending upwardly within the cylindrical member 23 and having an axial opening 25 through which a retaining bolt 26 extends.

Suitable means are provided for frictionally engaging the tapered surface 2l'of the cylindrical member 23. In the form of construction selected to illustrate one embodiment of the invention, a split sleeve element 2 8 is employed for this purpose. The sleeve element is tapered toward its lower end to conform to the inner surface of the cylindrical member 2| with which it frictionally engages. In order that the upper portion of. the 26 sleeve that does notcontact the tapered surface of the cylindrical member shall contract with the lower portion that does contact said surface when the sleeve is depressed,-the sleeve is made slightly thinner adjacent its upper end as at 40. 30

In order that all portions of the sleeve shall bend equally when the same is contracted, the portions of th'e'sleeve adjacent to the slot 29 are made comparatively thin as at 3| and 32 and the sleeve increases to its maximum thickness directly op- 35- posite the slot, as at 33.

The sleeve element. is provided with a plu-.-

. rality of radially extending bearing lugs or projections at its upper .end. These lugs or projections are adaptedto support a cap member or supporting plate 30 which in turn supports the bolster l5 of the truck. Whatever inclined position the supporting plate may be caused to take tilted in its vertical movement during use even though the bolster should'tilt or rock, suitable means are provided for compensating for any tilting or rocking of the bolster. In the construction shown, the projections or lugs 34 are provided with curved surfaces on their upper sides. These curved surfaces-are so constructed that they will remain in contact with the plate 30 even though said plate be tilted. In other words, the curved surfaces of these lugs constitute in effect portions of a sphere or ball with said surfaces curving downwardly toward the outer ends of said lugs.

The supporting plate or member 30 for supporting the car bolster 5 comprises a plate 31 having its central portion depressed to form a hollow cylindrical projection or boss 38 having an axial opening 39 therein through which the bolt 26 extends, as shown in Fig. 2 of the drawing. In the operation of the device, the contraction of the sleeve member 28 necessarily causes the lugs 34 to move relative to the under surface of the supporting plate 30 and in order that the lugs shall move evenly, means are provided to offer a minimum resistance to this movement. In the form of construction shown, which is by way of example only, the plate 3'1 is provided with an ahnular inclined surface .4| extending about the boss 38. This surface is adapted to be engaged by the curved surfaces of the lugs 34 when the bosses are assembled. The inclined surfaces 35 on the lugs 34 engaging the inclined surfaces 4| onthe plate tend to assist the contraction of the sleeve 28 when the bolster is forced downwardly. The lugs 34 are symmetrically arranged with reference to the split in the sleeve, whereby the two lugs adjacent the split will move uniformly during the compression of the unit.

A spring seat 42 having a horizontal portion 43 and a vertical peripheral flange 44 extends about the upper end of the sleeve element 28 and is adapted to engage the lower surface of the lugs 34. The flange 44 is adapted to engage the lugs 35 for positioning the seat on the sleeve element. The spring I9 is inserted between the spring seat 43 and the lower base plate 22 for returning the boss to normal position after compression. When the parts are in operative position, as shown in Figs. 1 and 2, and the bolster is depressed, the unit is compressed by causing the sleeve 28" to slide downwardly into the cylindrical member 2|,

downwardly, the sleeve 28 will be compressed radially. The resistance to compression of the sleeve will develop considerable friction between the contacting surfaces of the sleeve 28 and cylindrical member 2|. This frictional resistance together with the resistance to compression of the spring I9 will absorb the shock and will check and finally stopthe downward movement of the bolster |5. During the downward movement of the sleeve element it will contract, thus causing the lugs 34 adjacent to the slot 29 to move inwardly. The inclined surface 4| on the supporting plate 30 with which the lugs 34 engage will facilitate this movement. The spring i9 .which has sufficient capacity to return the parts to normal position after compression will react when the bolster reaches the limit of its downward movement after each shock. The capacity of the unit may be varied within extremely wide limits. By tapering the sleeve element 28 and its cooperating. friction surface 21 in the cylindrical member 2| at an angle more acute, the capacity is increased materially. Making this angle less acute decreases the capacity. With the increase in the acuteness of the angle, the capacity of the spring l9 should also be increased, as otherwise a point may be reached where the wedging action may become so great that upon release the spring may not .possess sufficient energy to release t e frictlon elements.

The parts are preferably so constructed that the units are interchangeable with the conventional springsthat are at present employed for supporting the truck bolster.

In the form of construction shown in Fig. 5, this construction differs from that just described in that the base plate is separate from the remaining elements. As shown, the supporting plate 46, the spring seat 41, the split friction sleeve 48, the bolt 49 and the spring 5| are substantially the same as the construction shown in Fig. 2. The base member 52 is provided with a hollow boss 53 having an axial opening therein for receiving the lower end of the bolt 49. Extending about the boss 53 is a recess 54 having a curved or concave wall 55 on which is seated the lower end of a friction sleeve 56. The friction sleeve 56 is provided with a plurality of radial projections 51 which correspond to the radial projections 35. of the sleeve member 28. These projections are provided with curved lower surfaces 58 which are adapted to engage the curved or concave wall 55. A spring seat 59 is interposed between the spring 5| and radial projections 51. In the operation of the device, the radial projections 51 and curved or concave wall 55' perform the function of a ball and socket joint which will permit a slight angular movement of the friction sleeve 56 relative to the base plate 52, thereby insuring the parallelism of the plates 46 and 52 under all conditions.

The spring 5| is placed in position under tension and in the operation of the device the spring will tend to restore the parts 'to normal position after the device has been compressed, and w'll also tend to restore the parts to normal position after the plate 46 has been moved laterally relative to the plate 52.

It is thought from the foregoing taken in con-' tails of construction may be made without deandsince the opening in said member tapers parting from the spirit and scope of the appended claims.

I claim as my invention:

1. A railway truck bolster supporting unit comprising an upper plate having surfaces on its lower side inclined upwardly and inwardly, a lower plate, telescopic friction elements between said plates, one of said elements having a plurality of laterally projecting arms on its upper end, said arms having their upper surfaces extending outwardly and downwardly for engaging said inclined surface and a spring between said plates for returning the parts to normal position after release.

2. In a railway truck bolster supporting unit, an upper plate, a lower plate, a cylindrical hollow member rigidly secured to and extending upwardly from said lower plate, the interior walls of said member tapering downwardly, a tapered split sleeve element telescopically mounted in said member and frictionally engaging the same, the upper end of said element having laterally extending means engaging said upper plate, a spring surroundingsaid member and element and seated on said lower plate, and a spring seat having an annular horizontal portion interposed between said spring and said means, said seat provided with an upstanding'fiange about its inclined friction surface for engaging the inbase plate having a cylindrical member extending axially upward therefrom and having an axial opening therein tapering downwardly, a perforated hollow boss extending upwardly within said member, a top supporting plate having a perforated hollow boss extending downwardly from its central portion, a tapered split sleeve member frictionally engaging said tapered opening and engaging said top supporting plate, a spring seated on said base plate and surrounding said cylindrical and sleeve members, a spring seat between said spring and supporting plate and in engagement with said spring, means on said sleeve engaging said spring plate, and a bolt extending through the perforations of said bosses for limiting the expansion of said unit.

4. In a bolster spring construction, a lower plate forming a springseat, said plate having a raised hollow boss provided with an axial opening in its bottom wall, a cylindrical friction element surrounding said boss and extending upwardly beyond'the same, said element having its inner surface tapering downwardly, a split sleeve friction member frictionally engaging the inner tapered surface of said friction element, said sleeve having friction lugs at its upper end extending radially outward and having their upper surfaces inclined downward and outward, an upper plate having a flange and a depressed hollow boss provided with an axial opening in its bottom wall, said upper plate having an annular clined surface of said frictionlugs, a spring seat engaging said friction lugs, a spring between said seats and a bolt extending through said axial;

openings for limiting the expansion of said spring. 5. A car bolster support comprising a pair of plates each having a curved surface on its inher face, a pair of telescopic friction sleeves between said plates, said sleeves each having means on its outer end, provided with convex surfaces for forming ball and socket joint with the curved surface of the corresponding plates whereby said plates will remain in parallelism even though they are temporarily out of alignment and resilient means for restoring the parts to normal position after release.

6. A resilient supporting unit for railway trucks comprising a'pair of cylindrical telescoping friction members, one of said members being tapered, one of said members having a unitary head with a convex outer surface, a flange associated with the other member, and a spring encircling said telescopic members between said flange and head, and a cap member having a curved bearing surface for engaging said convex surface for forming therewith a ball and socket joint, and means for limiting the expansion of said unit and for seating said bearing surface on said convex surface during the operation of the unit.

- MARCHAND B. HALL. 

